Contribution of Dysregulated DNA Methylation to Autoimmunity

Epigenetic mechanisms, such as DNA methylation, histone modifications, and non-coding RNAs are known regulators of gene expression and genomic stability in cell growth, development, and differentiation. Because epigenetic mechanisms can regulate several immune system elements, epigenetic alterations have been found in several autoimmune diseases. The purpose of this review is to discuss the epigenetic modifications, mainly DNA methylation, involved in autoimmune diseases in which T cells play a significant role. For example, Rheumatoid Arthritis and Systemic Lupus Erythematosus display differential gene methylation, mostly hypomethylated 5′-C-phosphate-G-3′ (CpG) sites that may associate with disease activity. However, a clear association between DNA methylation, gene expression, and disease pathogenesis must be demonstrated. A better understanding of the impact of epigenetic modifications on the onset of autoimmunity will contribute to the design of novel therapeutic approaches for these diseases.     

Vascular-confined multi-passage discoidal nanoconstructs for the low-dose docetaxel inhibition of triple-negative breast cancer growth

Taxane efficacy in triple negative breast cancer(TNBC)is limited by insufficient tumor accumulation and severe off-target effects.Nanomedicines offer a unique opportunity to enhance the anti-cancer potency of this drug.Here,1,000 nm×400 nm discoidal polymeric nanoconstructs(DPN)encapsulating docetaxel(DTXL)and the near infrared compound Iipid-Cy5 were engineered.DPN were obtained by filling multiple times cylindrical wells in a poly(vinyl alcohol)template with a polymer mixture comprising poly(lactic-co-glycolic acid)(PLGA)and poly(ethylene glycol)diacrylate(PEG-DA)chains together with therapeutic and imaging agents.The resulting“multi-passage”DPN exhibited higher DTXL loading,Iipid-Cy5 stability,and stiffness as compared to the conventional"single-passage"approach.Confocal microscopy confirmed that DTXL-DPN were not taken up by MDA-MB-231 cells but would rather sit next to the cell membrane and slowly release DTXL thereof.Empty DPN had no toxicity on TNBC cells,whereas DTXL-DPN presented a cytotoxic potential comparable to free DTXL(IC₅₀=2.6 nM±1.0 nM vs.7.0 nM±1.09 nM at 72 h).In orthotopic murine models,DPN accumulated in TNBC more efficiently than free-DTXL.With only 2 mg/kg DTXL,intravenously administered every 2 days for a total of 13 treatments,DTXL-DPN induced tumor regression and were associated to an overall 80%survival rate as opposed to a 30%survival rate for free-DTXL,at 120 days.All untreated mice succumbed before 90 days.Collectively,this data demonstrates that vascular confined multi-passage DPN,biomimicking the behavior of circulating platelets,can efficiently deliver chemotherapeutic molecules to malignant tissues and effectively treat orthotopic TNBC at minimal taxane doses.     

Effect of graft copolymerization of mixtures of acrylamide and methyl methacrylate on mechanical properties of jute fibers of different compositions

The role of persulfate-induced graft copolymerization of mixtures of acrylamide and methyl methacrylate at 50°C in modifying mechanical properties of jute fibers of different compositions was studied in a limited aqueous system following a pretreatment technique. Results obtained indicate that such a process admits a good scope for modification of mechanical properties of jute fiber depending on degree of grafting achieved and compositional variations of (1) the feed monomer mixture and (2) the multiconstituent jute itself, consequent to selective removal of lignin and hemicellulose to different extents from the fiber. Low to moderate removal of hemicellulose is more effective than a similar degree of removal of lignin from jute in rendering the fiber more amenable to vinyl grafting using the mixed monomer system without being adversely affected with respect to tensile properties. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1139–1147, 1998     

Influence of Kevlar Hybridization on Dielectric and Conductivity of Bamboo Fiber Reinforced Epoxy Composite

In a motive to develop a natural fiber-based dielectric material, bamboo fiber-reinforced epoxy composite is fabricated using hand layup technique and hybridized with Kevlar K29 fiber to enhance its properties. Dielectric and conductivity studies are performed using LCR meter on the composite samples as a function of frequency (100 Hz-1 MHz) and temperature (22–120°C). From the experiment, it is observed that the dielectric properties of bamboo-based natural composite are significantly enhanced by Kevlar hybridization. And also the influence of variation in frequency and temperature on the electrical properties i.e. dielectric and conductivity of the fabricated composite was studied. The morphological study is also carried out using scanning electron microscope (SEM).     

Microwave-assisted route for synthesis of nanosized metal oxides

Microwave-assisted route for the synthesis of nanomaterials has gained importance in the field of synthetic technology because of its faster, cleaner and cost effectiveness than the other conventional and wet chemical methods for the preparation of metal oxide nanoparticles. In the present work, synthesis of metal oxide nanoparticles viz., γ-Fe₂O₃, NiO, ZnO, CuO and Co-γ-Fe₂O₃ were carried out by microwave-assisted route through the thermal decomposition of their respective metal oxalate precursors employing polyvinyl alcohol as a fuel. The metal oxide nanoparticles are then characterized for their size and γ to α (in γ-Fe₂O₃) transition and structure by employing powder X-ray diffraction (XRD) pattern, high-temperature X-ray diffraction (HTXRD) pattern and Fourier transform infrared (FT-IR) spectral studies. The morphology of the samples ranged from nanorods to irregular-shaped particles for different metal oxide samples on the basis of scanning electron microscopy and transmission electron microscopy images. Frequency-dependent dielectric study of the ferrite samples (γ-Fe₂O₃ and Co-Fe₂O₃) showed a similar behaviour, where the dielectric constant decreased rapidly with increase in frequency. Possible explanation for this behaviour is given.     

A perspective on functionalizing colloidal quantum dots with DNA

This perspective provides an overview of the techniques that have been developed for the conjugation of DNA to colloidal quantum dots (QDs), or semiconductor nanocrystals. Methods described include: ligand exchange at the QD surface, covalent conjugation of DNA to the QD surface ligands, and one-step DNA functionalization on core QDs or during core/shell QD synthesis in aqueous solution, with an emphasis on the most recent progress in our lab. We will also discuss emerging trends in DNA-functionalized QDs for potential applications.      

Electro-Fenton treatment of synthetic organic dyes: Influence of operational parameters and kinetic study

This work investigates oxidative decolorization of two different dyes, Methylene blue and Titan yellow in aqueous solution using an environmentally friendly advanced electro-chemical oxidation (electro-Fenton) process. The effect of operating conditions like H₂O₂ concentration, current density, initial dye concentration was studied in a batch stirred cell. Individual decolorization decay kinetics for both dyes was investigated. The second-order absolute rate constants (L mol^?1 s^?1) between hydroxyl radical and dye have been calculated from experimental data by fitting it to the decolorization model. The apparent kinetic constants, k _app (s^?1) for Methylene blue and Titan yellow dye decolorization were also determined. The experimental data showed a good fit to the theoretical model, which can predict data in a wide range of % dye decolorization. This process also reduces COD of the dye solution, and the unit energy demand (UED) in kWh/kg COD removed for different electrical current has been reported.